The present invention relates to a tray that can mount to a ladder or similar device to provide a work surface on which objects can be placed, and particularly, to a tray that can be attached to and detached from a step stool frame without using any tools or mounting hardware separate from the tray. More particularly the present invention relates to a detachable tray for a step stool that, once mounted to the step stool, can pivot between a use position extending generally horizontally away from a frame of the step stool and a storage position lying against the frame of the step stool.
Trays that attach to ladders and step stools to provide a work surface on which objects can be placed are known in the art. Some trays that attach to ladders and step stools are rigidly mounted to a frame of the ladder or step stool so that the tray is fixed in a single position relative to the ladder or step stool. See, for example, U.S. Pat. Nos. 5,342,008 to Kay and 4,730,802 to Chatham et al. Other trays that attach to ladders and step stools may include movable linkage assemblies that connect the tray to the ladder or step stool. Such movable linkage assemblies typically can be adjusted to pivot the tray between a horizontal position and a storage position. See, for example, U.S. Pat. No. 5,120,013 to Sweeney.
Some trays that attach to ladders and step stools may include separate pieces that cooperate to form a single tray. See, for example, U.S. Pat. No. 4,979,590 to Bailey which discloses a platform for a ladder or step ladder including a first tray portion, a second tray portion pivotally coupled to the first tray portion and movable from a storage position where the tray portions overly each other to a work position where the second tray portion forms an extension to the first tray portion to provide a tray.
What is needed is a one-piece tray that can mount to a frame of a ladder, step stool, or similar device to form a ladder assembly and that can pivot relative to the frame between a horizontal use position and a storage position while mounted to the frame. A tray that can be mounted to a step easily by consumers without tools and that includes a surface engaging the frame to support the tray in the use position wherein a shelf of the tray extends generally horizontally away from the frame and a surface engaging the frame to support the tray in the storage position wherein the shelf of the tray is positioned to lie adjacent to the frame would provide many advantages to consumers.
According to the present invention, a tray is provided for attachment to and detachment from the frame of a ladder such as a step ladder or step stool. The tray includes a shelf having a curved surface that provides rotative bearing engagement between the tray and the ladder frame during pivoting movement of the tray relative to the ladder frame between a use position in which the shelf extends horizontally away from the ladder frame and a storage position in which the shelf is positioned to lie adjacent to the ladder frame. The curved surface is configured to retain the tray in engagement with the ladder frame during pivoting movement of the tray between the use and storage positions.
The tray further includes a support arm fixed to the shelf and arranged to engage the ladder frame to support the tray in both of the use and storage positions. The support arm includes a first support surface that engages the frame when the tray is in the use position to support the tray in the use position. The support arm also includes a second support surface that engages the frame when the tray is in the storage position to hold the tray in the storage position. The first support surface of the support arm is horizontally and vertically spaced apart from the curved surface of the shelf.
In preferred embodiments, a one-piece tray is mountable to a frame of a step stool without using tools or additional hardware and is detachable from the step stool frame without using tools. The step stool includes a U-shaped frame member having a horizontal strut and a pair of spaced-apart legs that extend generally downwardly from opposite ends of the horizontal strut. The tray includes a shelf that is formed to include a top work surface, a front edge, a rear edge, a first side, and a second side. In addition, the tray includes a first support arm appended to the first side of the shelf and a second support arm appended to the second side of the shelf.
The tray also includes a pair of spaced-apart mounting clips appended to a bottom portion of the shelf of the tray adjacent to the front edge of the shelf. The mounting clips are formed so that the tray can mount to the horizontal strut of the U-shaped frame member between the downwardly-extending legs. Each mounting clip cooperates with the bottom portion of the shelf to define a curved surface for engaging the horizontal strut of the step stool to provide rotative bearing engagement between the tray and the step stool frame during pivoting movement of the tray relative to the step stool frame between the use and storage positions.
The horizontal strut has a round cross-section and the mounting clips are generally C-shaped so that the mounting clips grasp the horizontal strut at the curved surface defined by the mounting clips and bottom portion of the tray to allow the tray to pivot relative to the frame member between the horizontal use position and the storage position. The tray can be attached to and detached from the horizontal strut of the step stool easily by a consumer without using tools or additional mounting hardware merely by moving the tray relative to the step stool to engage or disengage the tray mounting clips and the horizontal strut of the step stool.
Each of the legs of the U-shaped frame member includes a rear surface facing away from a person standing on the step stool and each of the first and second support arms includes a front support surface that engages respective rear surfaces of the legs to support the tray in the use position. When the tray is in the use position, the top work surface of the shelf of the tray faces generally upwardly and a portion of the bottom surface adjacent to the front edge of the shelf rests upon a top surface of the horizontal strut of the U-shaped frame member.
Each of the legs of the U-shaped frame member includes a front surface facing toward a person standing on the step stool. Each of the first and second support arms also includes a top support surface that faces generally upwardly when the tray is in the use position. Each of the top support surfaces of the first and second support arms engage respective front surfaces of the legs when the tray is in the storage position so that the tray hangs generally downwardly from the horizontal strut of the U-shaped frame member in parallel relation with the legs of the U-shaped frame member. In addition, the shelf of the tray is positioned to lie generally between the legs of the U-shaped frame member so that the first and second sides of the shelf are adjacent to respective legs of the U-shaped frame member, when the tray is in the storage position.
The first and second support arms are appended to first and second spacers, respectively, which are coupled to respective first and second sides of the shelf. The spacers position each support arm in an offset arrangement so that the first and second support arms are spaced apart from the bottom surface of the shelf of the tray. The offset arrangement allows the support arms to engage the rear surface of the frame member legs when the tray is in the use position and to engage the front surface of the frame member legs when the tray is in the storage position. As a result of the offset configuration of the first and second support arms relative to the shelf of the tray, the tray must be pivoted over the top of the horizontal strut through an angle that is greater than one hundred eighty degrees (180.degree.) when the tray is moved between the use and storage positions.
Additional objects, features, and advantages of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of a preferred embodiment exemplifying the best mode of carrying out the invention as presently perceived.